A device that provides you with a computer-operable display; can be worn or surgically implanted right on your own eyes.

I love the details in this sort of technovelgy - not just the device, but a description of how the device is used intentionally by a user, and how others might take advantage of the device. This sounds just like what our world's friendly corporations might do.

You could get a phantoscopic system planted directly on your retinas...You could even get telaesthetics patched into your spinal column at key vertebrae. But this was said to have its drawbacks ... it was rumored that hackers for big media companies had figured out a way to get through the defenses that were built into such systems, and run junk advertisements in your peripheral vision (or even spang in the ... middle all the time - even when your eyes were closed. Bud knew a guy like that who's somehow gotten infected with a meme that ran advertisements for roach motels, in Hindi, superimposed on the bottom right-hand corner of his visual field, twenty-four hours a day, until the guy whacked himself.

Actually, there is already a real phantoscope. It was an early device for viewing motion pictures developed in 1895 by Charles Francis Jenkins. It was a variation on the Edison Kinetoscope. It was renamed the Vitascope, and further developed by Thomas Edison.